﻿ C++ : Sort an array using the Insertion sort algorithm

# C++ Insertion sort algorithm Exercise: Sort an array of elements using the Insertion sort algorithm

## C++ Sorting: Exercise-9 with Solution

Write a C++ program to sort an array of elements using the Insertion sort algorithm.

Sample Solution:

C++ Code :

``````// Including necessary C++ libraries
#include <algorithm>
#include <iostream>
#include <iterator>

// Function to perform insertion sort algorithm with a custom predicate
template <typename RandomAccessIterator, typename Predicate>
void insertion_sort(RandomAccessIterator begin, RandomAccessIterator end,
Predicate p) {
// Iterate through each element in the range [begin, end)
for (auto i = begin; i != end; ++i) {
// Rotate the sorted part to insert the current element at its correct position
std::rotate(std::upper_bound(begin, i, *i, p), i, i + 1);
}
}

// Function to perform insertion sort algorithm using the default 'less' comparison
template <typename RandomAccessIterator>
void insertion_sort(RandomAccessIterator begin, RandomAccessIterator end) {
// Utilizing insertion_sort function with 'less' as the default comparison
insertion_sort(
begin, end,
std::less<
typename std::iterator_traits<RandomAccessIterator>::value_type>());
}

// Main function
int main() {
// Initializing an array of integers for sorting
int a[] = {125, 0, 695, 3, -256, -5, 214, 44, 55};

// Displaying the original numbers in the array
std::cout << "Original numbers:\n";
std::copy(std::begin(a), std::end(a), std::ostream_iterator<int>(std::cout, " "));
std::cout << "\n";

// Sorting the array using insertion_sort function
insertion_sort(std::begin(a), std::end(a));

// Displaying the sorted numbers after insertion sort
std::cout << "Sorted numbers:\n";
std::copy(std::begin(a), std::end(a), std::ostream_iterator<int>(std::cout, " "));
std::cout << "\n";

// Returning 0 to indicate successful execution
return 0;
}
``````

Sample Output:

```Original numbers:
125 0 695 3 -256 -5 214 44 55
Sorted numbers:
-256 -5 0 3 44 55 125 214 695
```

Flowchart:

C++ Code Editor: